It's claimed commuters using the Thameslink rail line which runs from Bedford to London may have to wait longer for improved services.
While changes have been made, including longer trains and the current redevelopment of Blackfriars and London Bridge stations, the National Audit Office is concerned progress is too slow.
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Cloud thickening tonight with rain spreading eastwards later.
A mixture of sunny spells and isolated showers this afternoon.
Police think that one of the men involved in last week's abduction attempt at RAF Marham was given a black eye.